سلام
الان من کد زیر رو نوشتم،‌میدونم اشکال داره ولی نمیدونم کجا !!!

کد:
<?php
$con = mysql_connect("localhost", "root", "") 
or die(mysql_error());
mysql_select_db("mydatabase", $con) 
or die(mysql_error());
$result = mysql_query("SELECT * FROM xfmf9_private_messages WHERE msg_sender='$msg_sender'", $con)
or die(mysql_error()); 


$msgsender = $_POST['msg_sender'];


while ($row = mysql_fetch_array($result)){
    $id = $row['msg_id'];
    $name = $row['msg_sender'];
    $family = $row['msg_receiver'];
    $age = $row['msg_text']; 
        echo "$id و $name و $family و  $age";
}
mysql_close($con);
?>

<form action="" method="POST">
    <input type="text" name="msg_sender"  id="msg_sender" value="">
    <input type="submit" value="ok">
</form>